U.S. patent number 5,368,317 [Application Number 08/005,374] was granted by the patent office on 1994-11-29 for fire truck torque box chassis frame.
This patent grant is currently assigned to Emergency One, Inc.. Invention is credited to Jeffrey D. Aiken, William F. McCombs.
United States Patent |
5,368,317 |
McCombs , et al. |
November 29, 1994 |
Fire truck torque box chassis frame
Abstract
A torque box chassis frame for firefighting vehicles or the like
constituting a platform for extendible aerial ladders. The vehicle
torque box chassis frame includes elongated lower and upper members
significantly spaced from each other having rigid bracing structure
interposed therebetween resulting in a rigid elongated box of
significant rectangular cross section dimension. The torque box
chassis frame rear end is defined by a rigid ladder turntable
support including its own vertical rigid columns, and spaced
outrigger support tubes for receiving hydraulic outrigger jacks are
integrally defined on the torque box chassis frame to provide firm
support of the torque box upon the ground eliminating the influence
of the vehicle suspension system.
Inventors: |
McCombs; William F. (Ocala,
FL), Aiken; Jeffrey D. (Ocala, FL) |
Assignee: |
Emergency One, Inc. (Ocala,
FL)
|
Family
ID: |
21715526 |
Appl.
No.: |
08/005,374 |
Filed: |
January 15, 1993 |
Current U.S.
Class: |
280/4; 182/66.1;
280/6.153; 280/797 |
Current CPC
Class: |
B62D
21/00 (20130101); E06C 5/04 (20130101); A62C
27/00 (20130101) |
Current International
Class: |
B62D
21/00 (20060101); E06C 5/00 (20060101); E06C
5/04 (20060101); A62C 027/00 () |
Field of
Search: |
;280/4,6.11,6.12,6.1,796,797,800,799,790,789,786,781,783,475
;182/2,64,65,67 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Culbreth; Eric D.
Assistant Examiner: Boehler; Anne Marie
Attorney, Agent or Firm: Beaman & Beaman
Claims
We claim:
1. A fire truck torque box for supporting an extendible ladder
comprising, in combination, an elongated box having a pair of
elongated spaced lower members, a pair of elongated spaced upper
members spaced directly above said lower members wherein said
members together transversely define a rectangular box having a
front end, a rear end, vertical lateral sides, a bottom, and a top,
said lower members each extending the length of said box and
located adjacent said bottom and one of said lateral sides, said
upper members each being located adjacent said top and one of said
lateral sides, said box defining a rigid structure, a first pair of
elongated outrigger support tubes rigidly affixed to said lower
members adjacent said box front end and below said box bottom, a
second pair of elongated outrigger support tubes rigidly affixed to
said lower members adjacent said box rear end and below said box
bottom, the length of said pairs of outrigger support tubes being
substantially perpendicular to the length of said box and the
length of said lower members, said box lateral sides being formed
of rigid first bracing comprising steel plates extending between
said lower and upper members located on a common box lateral side
and welded thereto and enclosing the associated side, said box
bottom being formed by rigid second bracing comprising a steel
plate extending between said lower members and welded thereto, said
box top being formed by rigid third bracing extending between said
upper members, an extendible hydraulic outrigger jack located
within each of said outrigger support tubes said box rear end being
integrally defined by a ladder support turntable including vertical
columns rigidly affixed to and extending upwardly from said lower
members and affixed to said lateral side plates and an upper plate
rigidly affixed to said upper members and said columns defining a
ladder support ring.
2. In a fire truck torque box as in claim 1, said third rigid
bracing comprising elongated steel truss members each having ends,
the length of said truss members being obliquely related to the
length of said box and the ends of said truss members being welded
to said upper members.
3. In a fire truck torque box as in claim 1, said lower members
comprising channels, and said upper members comprising rectangular
tubes.
4. In a fire truck torque box as in claim 1, said rigid box rear
end as defined by said ladder support turntable being open whereby
the interior of said box defines a ladder storage chamber
accessible through said open box rear end.
5. A fire truck torque box for supporting an extendible ladder
comprising, in combination, an elongated box having a pair of
elongated spaced lower members, a pair of elongated spaced upper
members spaced directly above said lower members wherein said
members together transversely define a rectangular box having a
front end, a rear end, lateral sides, a bottom, and a top, said
lower members each extending the length of said box and located
adjacent said bottom and one of said lateral sides, said upper
members each being located adjacent said top and one of said
lateral sides, said box defining a rigid structure, a first pair of
elongated outrigger support tubes rigidly affixed to said lower
members adjacent said box front end and below said box bottom, a
second pair of elongated outrigger support tubes rigidly affixed to
said lower members adjacent said box rear end and below said box
bottom, the length of said pairs of outrigger support tubes being
substantially perpendicular to the length of said box and the
length of said lower members, said box lateral sides being formed
of rigid first bracing comprising steel plates extending between
said lower and upper members located on a common box lateral side
and welded thereto, said box bottom being formed by rigid second
bracing comprising a steel plate extending between said lower
members and welded thereto, said box top being formed by rigid
third bracing extending between said upper members, an extendible
hydraulic outrigger jack located within each of said outrigger
support tubes and a ladder support turntable integrally and rigidly
affixed to said box at said rear end between said box bottom and
top whereby said turntable comprises an integral part of said box,
the distance between said upper members and between said lower
members being approximately 36 inches and the distance between said
lower members and the upper member directly thereabove being
approximately 36 inches whereby the transverse configuration of
said box is substantially equate.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to vehicle torque box chassis frames for
supporting extendible aerial ladders, such a frame being
particularly useful with firefighting vehicles.
2. Description of the Related Art
Firefighting vehicles such as ladder trucks include extendible
aerial ladders whereby the ladders may be raised and extended in
excess of one hundred feet, as may be required in fighting fires in
multiple story buildings, or conducting rescues therefrom.
Commonly, extending aerial ladders are hydraulically operated
whereby the ladder assembly may be lowered to a stored position,
and raised to an operative position. The ladder system consists of
a plurality of extension ladders, and when the ladders are
extended, and partially raised, significant bending forces are
applied to the frame of the support vehicle due to the weight of
the ladders, and any personnel or equipment supported thereon.
In order to stabilize vehicles supporting extendible ladder
systems, it is common to mount jack systems upon the vehicles which
extend laterally from the vehicle sides and include hydraulically
extendible jacks for engagement with the ground to stabilize these
vehicles during ladder extension. Most jack systems are attached to
the conventional vehicle structure, including the suspension
system, and while such jack systems do greatly improve the vehicle
stability during aerial ladder extension due to the high centroidal
moment of inertia imposed upon the vehicle by an extended aerial
ladder, the ultimate degree of stability desired has not been
achievable, and the height of extendible aerial ladders has been
limited due to the inability to provide as stable a ladder platform
as possible.
Efforts have been made to improve the stability of aerial ladder
platforms as formed on firefighting vehicles, as shown by the
assignee's U.S. Pat. No. 4,570,973. In this patent an elongated
torque box of generally rectangular transverse cross section
utilizes a plurality of braces and webs to form a substantially
rigid elongated box upon which the aerial ladder may be supported.
However, due to limitations in the vertical dimensions of the
torque box shown in U.S. Pat. No. 4,570,973, and structural
limitations due to the relationship of the ladder supporting
structure to the remainder of the torque box, optimum ladder
supporting characteristics were not achieved.
SUMMARY OF THE INVENTION
Objects of the Invention
It is an object of the invention to provide an integral aerial
torque box chassis frame which includes a turntable support for
aerial ladders wherein the torque box is capable of withstanding
high bending forces and provides a stable support platform for
extended aerial ladders.
Another object of the invention is to provide an integral aerial
torque box vehicle chassis free which includes a turntable support
for aerial ladders wherein extendible jack structure is integrally
formed with the torque box whereby the torque box may be directly
supported upon the ground without influence from the vehicle
suspension system.
Yet another object of the invention is to provide an integral
aerial torque box vehicle chassis frame constituting a platform for
extendible ladders wherein the torque box is supported upon
integral jack structure to provide stability, and the torque box is
open having an accessible rear end wherein ladders may be stored
within the torque box at a readily accessible location and
height.
An additional object of the invention is to provide an integral
aerial torque box vehicle chassis frame which may be readily
fabricated using conventional metal fabricating apparatus.
In the practice of the invention a pair of spaced parallel heavy
duty channel members are used to form the lower region of the
torque box, while a pair of elongated box cross section members are
vertically disposed above the channel members a significant
distance to provide sufficient resistance to bending moments.
Bracing elements in the form of sheet steel are interposed between
the upper and lower box and channel members located on a common
side of the box, while the lower channel members are interconnected
by a sheet steel bracing floor member. The upper members are
preferably interconnected by obliquely disposed truss members who
ends are welded to the upper members.
The rear end of the torque box constitutes a turntable support for
the aerial ladder apparatus. The turntable support is integral with
the other components of the torque box and includes a plurality of
columns having a box transverse cross section for supporting the
weight of the ladder assembly without deflection. The turntable
support defines the rear end of the torque box, and is open in
alignment with the length of the torque box chassis frame whereby
the interior of the torque box is accessible through the turntable
support and may serve as a chamber to receive ladders, or other
equipment.
The torque box chassis frame includes jack receiving tubes for
supporting hydraulic jacks. The front pair of the jack supporting
tubes is located adjacent the front region of the torque box below
the channel men,hers, while the rear pair of jack receiving tubes
is located below the turntable support. The jack tubes are of a
length perpendicularly disposed to the length of the torque box,
and the jack structure arms located therein are capable of being
laterally extended relative to the torque box length whereby the
hydraulic jacks formed on the ends of the extendible arms may be
lowered to engage the ground and directly support the torque box
chassis upon the terrain.
Due to the rigidity of the torque box chassis frame, the support of
the torque box on the terrain by the jacks bypasses the vehicle
suspension, and actually raises the vehicle slightly with respect
to the terrain whereby, during ladder operation, the entire vehicle
may be supported upon the jacks.
A torque box chassis frame constructed in accord with the invention
achieves a rigidity not heretofore attained, and provides a
platform for an extendible aerial ladder assembly which permits
aerial ladders to be extended to heights not previously
possible.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be
appreciated from the following description and accompanying
drawings wherein:
FIG. 1 is a side elevational view of a firefighting vehicle
utilizing the torque box chassis frame of the invention, the
extendible ladder assembly being partially illustrated,
FIG. 2 is a side elevational view of the torque box chassis frame,
per se,
FIG. 3 is a plan view of the torque box chassis frame of FIG.
2,
FIG. 4 is an elevational sectional view as taken along Section 4--4
of FIG. 3,
FIG. 5 is an elevational sectional view as taken along Section 5--5
of FIG. 3,
FIG. 6 is an elevational sectional view as taken along Section 6--6
of FIG. 3, and
FIG. 7 is a plan sectional view as taken along Section 7--7 of FIG.
2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The overall environment of a fire truck torque body in accord with
the invention is best represented in FIG. 1 wherein an entire fire
truck vehicle is illustrated. The fire truck basic component is the
frame or chassis 10 much of which forms the torque box construction
of the invention. The frame is supported on front wheels 12 and
dual rear wheels 14 which are attached to the frame 10 by
conventional suspension structure 16 which may be formed by leaf
springs, torsion springs or air bags, as is well known in the art.
The truck cab 18 is located at the front end of the frame 10 and
includes the engine and other vehicle control components, as well
as providing an enclosure for the firemen during transportation.
The usual pump structure 20 may be mounted upon the frame 10, and
other apparatus may be mounted upon the truck frame as is commonly
used with firefighting equipment.
As the inventive concept pertains to torque boxes used with aerial
ladders an extendible ladder 22 is pivotally mounted upon the
bracket 24 which is attached to the turntable 26 rotatably
supported upon the torque box by conventional bearings, not shown.
The vertical elevation of the ladder 22 is controlled by the
extendible hydraulic cylinder 28 interposed between the bracket 24
and the ladder structure, as well known. The particular type of
extendible ladder utilized with fire trucks employing the invention
does not form a part of the invention, and conventional ladder
arrangements may be used except that trucks utilizing the torque
box of the invention may employ ladders of greater extendible
length, and a greater number of sections, than extendible ladder
assemblies previously employed with mobile fire truck
platforms.
The frame 10 includes a section thereof designated as a torque box
30, the torque box constituting that portion of the vehicle frame
upon which the majority of bending forces are imposed when the
ladder 22 is extended.
The basic components of the frame 10 are a pair of substantially
parallel channel members 32 which extend the length of the vehicle.
The members 32 are in spaced relationship to each other and the
wheels 12 and 14 are located below the members 32 and support the
members through the wheel suspension apparatus.
The torque box 30, in addition to the members 32, is defined by the
elongated box members 34 located vertically above the rear portions
of the channel members 32 as will be appreciated from FIGS. 1 and
2. Vertical bracing colons 36 are interposed between the members 32
and 34 as being welded thereto, and the lateral sides of the torque
box 30 are defined by a sheet metal plate 38 extending between the
members 32 and 36 at each side of the torque box and the metal
plate 38 is welded to the members 32 and 34, as well as to the
columns 36. In this manner the sheet metal plate 38 rigidly
interconnects the members 32 and 34 in a vertical direction, and
the columns 36 which are also welded to the plate 38 prevent the
plate 38 from buckling. A sheet metal bottom plate 40, FIGS. 5 and
6, extends between the upper ends of the channel members 32 wherein
the plates 38 and plate 40 define a U-shaped configuration closing
in the sides and bottom of the torque box 30.
The upper portion of the torque box is defined by a plurality of
truss bracing members 42, FIG. 3, which extends between the box
members 34 having shaped ends whereby the men%bets 42 are welded to
the box members 34. By the use of the bracing members 42 the torque
box 30 is now defined of a rectangular cross sectional
configuration having the lateral side bracing plates 38, the bottom
plate 40, and the upper truss bracing members 42.
At its front end the torque box 30 is defined by wedge shaped
plates 44 extending from the box members 34 to the upper edges of
the channel members 32, and the plates 44 are welded to the
associated structure to further define an integral assembly.
At its rear end, the torque box 30 is defined by the ladder turn
table support 46. The turn table support 46 is defined by lateral
sheet plate sides 48 located between four steel box beam columns
50, FIG. 7, welded to the channel members 32 and extending
thereabove. The plate sides 48 are also welded to the columns 50,
and the columns 50 are also welded to the plates 38. At its upper
end, the turn table support 46 includes a rectangular frame 52
formed of steel box beams, and a thick two inch steel plate 54
having the circular opening 56 is welded to the upper turn table
frame 52. As the frame 52 is welded to the columns 50 and sides 48,
the turn table support 46 constitutes an integral rear end of the
torque box 30 so that all forces imposed upon the ladder turn table
support 46 will be directly imposed upon the torque box 30. The
ladder support structure, not shown in detail, is mounted upon the
plate 54 and extends into the opening 56, and such support
structure may include bearings, a large gear, motor, and other
apparatus for rotating the ladder turn table 26.
When extending the ladder 22 in a vertical direction, it is
necessary that the ladder platform be solidly supported upon the
ground, and such support is achieved through hydraulic jacks
rigidly associated with the frame 10 and torque box 30.
The jacks are mounted within outrigger supports of a rectangular
configuration for supporting the jack structure. The outrigger
support tubes are best illustrated in FIGS. 2 and 3.
A pair of front or forward jack support tubes 58 are welded to the
underside of the channel members 32 at a location directly below
the wedge plates 44. The tubes 58 are of an elongated configuration
as will be appreciated from FIG. 3, and the length thereof is at
right angles to the length of the torque box and channel members
32. The rear jack tubes 60 are also welded to the underside of the
channel members 32, and are located directly below the turntable
support 46. Bracing fillets 62 may be interposed between the jack
tubes and the channel members 32 to prevent twisting or
displacement of the jack tubes.
Hydraulic jack arm structure of a known type generally represented
at 64 is supported within the front tubes 58, and at their outer
ends the jacks include vertically disposed hydraulic cylinders 66
having pistons supporting a foot pad which engages the terrain. The
jack arms located within the front tubes 58 extend in an outrigger
manner in opposite directions from the torque box 30 to provide
lateral support of the front portion of the torque box in either
direction.
In a like manner, jack arm structure 68 is located within the rear
tubes 60 and include cylinders 70 having foot pads located at the
lower end of the cylinder pistons for engaging the terrain, the
jack arms 68 being extendible in opposite directions from the
torque box 30 in the same manner as the front jacks 64.
Also, a pair of front drop and lock jacks 74 are rigidly mounted on
frame 10 by brace gussets 76 which are vertically adjusted by
cylinders 78.
In practice, the vertical height of the torque box plates 38 is
approximately thirty-six inches, and the separation of the channel
members 32 and box members 34 is approximately 36 inches, while the
separation of the channel members 32 is of substantially equal
dimension, and as the plates 38, the bottom 40, and the truss
bracing members 42, as well as the turn table support sides 48,
columns 50 and frame 52 all define a large hollow box beam, the
torque box 30 is capable of withstanding very high bending forces
with minimal deformation as imposed thereon by the weight of the
ladder assembly 22. As the jacks 64, 68 and 74 are directly
connected to the torque box 30 the support of the torque box and
ladder assembly is directly by the terrain, and the vehicle
suspension is bypassed and is not a part of the ladder support.
Accordingly, the torque box 30 is directly supported upon the
terrain and as the jacks 64 and 68 can be longitudinally laterally
extended within their tubes 58 and 60, respectively, a wide, rigid,
broad base support for the torque box 30 is provided.
On uneven terrain, the extension of the cylinders 66, 70 and 78 may
actually lift the rear wheels 14, and/or front wheels 12, from the
terrain, depending upon the degree of the grade. However, upon the
jack cylinders being raised, and retracted into their associated
tubes, the weight of the vehicle frame 10 will be supported by the
wheels and their associated suspensions.
As will be appreciated from FIGS. 5 and 6, the configuration of the
torque box 30 is such that a rectangular space 72, FIG. 6, is
located between the plates 38 and above the bottom plate 40, and
this space is open at the rear through the turn table support 46
whereby ladders, hose, or other equipment may be readily stored
within the space 72 of the torque box 30, and easily and rapidly
removed therefrom for use.
The rigidity and stability of the torque box 30 utilizing the
aforedescribed concepts per, nits a heavier and longer ladder
assembly 22 to be mounted upon a vehicle than heretofore possible,
and the practice of the invention provides increased firefighting
and rescue capabilities.
It is appreciated that various modifications to the inventive
concepts may be apparent to those skilled in the art without
departing from the spirit and scope of the invention.
* * * * *